A laser-produced plasma sustained by a radiofrequency source

Summary form only given, as follows. The creation a high density plasma in atmospheric air is studied. The plasma is generated by photoionization of the organic seed molecule tetrakis(dimethylamino)ethylene (TMAE) and is sustained by RF coupling through the use of an antenna. The coupled power is a function of antenna configuration, plasma density, working gas: and applied magnetic field. Previous studies have utilized these antennas to couple power to the plasma through the inductive mode of operation. The inductive source operates by coupling power to the plasma through collisional ohmic heating of the wave energy. Helicons have shown to be very efficient sources in the low pressure argon regime with densities of the order 4/spl times/10/sup 13/ cm/sup -3/ with only 600 W of power in a 5 cm radius tube. The VUV laser in this experimental has created plasmas of order 10/sup 14/ cm/sup -3/. The high density gives an initial condition which allows higher radiation resistance and more power to couple to the plasma. The computer codes ANTENA2 and MAXEB are used to optimize the experiment and interpret results. The effects of adding separate air constituents will be studies as a function of neutral pressure, and will be compared to the effects of adding inert gases. Both highly collisional power absorption and noncollisional Landau effects will be investigated.